When to neck size?

[Harvey_NW]

The whole problem IMO with FL sizing is that the specs reduce the size of your cartridge to the smallest dimension that will fit every chamber of that caliber. If your chamber is on the large side, bang, automatic sloppy head spacing.

This is only if you're setting a FL die up to cam over against the shellholder and size the case back to min SAAMI specs, but you can measure with a headspace gauge and set a FL die up to minimally push shoulders back and size the body portion just enough to run smooth in the chamber it was fired in. Essentially the same process as using a neck die, then shoulder or body die, but in 1 stroke.

 

[35WhelenAI]

Correct, the above post is taking advantage of the fact you don't have to screw the sizing die down until it touches the shell holder, which at that point sizes full length. That's what I was saying in post #41, and has been mentioned in other posts as well. Screw the die down a bit at a time until cases chamber freely and smoothly, usually well above die contact with the shell holder.

 

[35WhelenAI]

My current procedure is to cycle every piece of fire formed brass that I’m planning on reloading through the rifle it came out of. If the bolt closes easily, I just neck size, check length and trim as needed. I’m currently not doing a lot of trimming because it’s not required. and only run that brass in the rifle it came out of. I anneal after every 3 firings.

Verify the cases chamber by rotating them 90° or so at a time in different orientations. If the case goes back in the way it came out of the chamber or close to it, it's going to check out as ok. However I've had them chamber fine the first time, rotate them 90°, 180° and it gets stiff.

 

[nm.otter]

The whole problem IMO with FL sizing is that the specs reduce the size of your cartridge to the smallest dimension that will fit every chamber of that caliber. If your chamber is on the large side, bang, automatic sloppy head spacing. My experience has been that full length sizing caused my brass to grow in length pretty fast, meaning I had to trim necks more often. This was for 30-06, .243, and 7-08.

...all of which have tapered cases, shallow shoulder angles, and loose SAAMI specs.

Modern cartridges are different.

 

[RME]

Perhaps my reloading lexicon is antiquated or just off from the terminology in common use these days. To me, Full Length Sizing is taking brass back to where it started for length dimensions, as in "full length", versus what I would call a Shoulder Bump, which would be allowing a case to first fully form to the chamber and then minimally sizing off of that measurement, which generally leaves at least a portion of the case not fully engaged in the sizing die.

You're absolutely right, to me it's just a matter of context. If the discussion is about dies and somebody says they using a full length die I assume they they're referring to the type rather than how the die is set up. If the discussion is specifically about die set up and somebody says they're full length sizing then I'd conclude they're talking about fully sizing the case as opposed to "partial FL sizing" (shoulder bumping).